We’re a community of members from more than 60 countries and 48 states that come together to share a passion for coral reef marine life and learn and see more!

The Demoiselles – Reef Gems

The demoiselles (genus Chrysiptera) are among the most beautiful of all the damselfishes. It also contains some of the smallest and most overlooked pomacentrids. This Pictorial Profile examines most of the species in this genus.

Clown Blennies

There are many fishes on the reef that can bring a smile to the face of a human observer. But few have as comical a countenance as the blennies.

Antipredation Behavior of Reef Fishes

Many reef fishes spend a considerable amount of time and energy trying to avoid being eaten. In this series of articles, we will look at the antipredation strategies and tactics employed by fishes to avoid their piscine neighbors.

Nudi Falls Virtual Dive

Make a “Virtual Dive” on one of Lembeh’s most popular dive sites — Nudie Falls.

Education can be fun!

School with the Best CoralRealm University Online, an extension of CoralRealm.com. Our mission is to provide our members with high-quality information and resources to make learning fun and engaging…

Marine Life Encyclopedias

Search our Reef Fish or Shark Encyclopedias containing more than 1200 descriptions and photos! Learn their habitats, behaviors and much more!

Crusty Cleaners – Crustaceans that clean fish

Did you know there are shrimps in the “cleaning business”? This interesting feature article details the cleaning behavior of many types of shrimps. Included is a photo gallery with information on biology and behavior.

Deepsea Sharks

Command the CoralRealm submersible on a mission to investigate deepsea sharks. Loads of information on biology and numerous photos. Some of the weirdest sharks in the sea! No experience necessary!

Dazzling Dottybacks

Although often overlooked because of their small size, the dottybacks are some of the most colorful and interesting fishes on Indo-Pacific coral reefs. Learn more about them here!

Test Your Fish & Shark ID Skills!

Enhancing your knowledge of reef fishes is the best way to get more enjoyment out of every dive. The more you learn, the more you’ll see on every dive. Guaranteed.

CoralRealm is making it easier for you to learn the names and fascinating facts about reef fishes that inhabit the coral reef. Every day, you’ll be able to check out the photo of a new, featured reef fish.

Test your knowledge by trying to identify the species by common name. We’ll provide you with the correct name and much more! Our detailed profiles include information on habitats, feeding, reproduction, behaviors, diver interaction, distinguishing characteristics and best places to see.

This is a great way to sharpen your fish ID skills!

Table of Content

Reef Fish Guide Introduction

The Transformers!

They’re for real!

Reef fishes use a variety of defense mechanisms to protect themselves from predators. Some fishes use unique color patterns as camouflage. Other fishes transform their body shape or produce toxic substances to become less appetizing meals. The puffers use a combination of these defense mechanisms to protect themselves.

Sleeper Gobies

The goby family is the largest on coral reefs. Learn about the sleeper gobies, a group that exhibits fascinating feeding and reproductive behavior. Includes links to 12 species profiles.

The Freckled Moray

Keep Your Eyes Open for this Eel Oddity

Learn about a clan of banded morays, known as the reticularis group and their unusual life-style.

Comet Reproduction

Calloplesiops altivelis is a beautiful but reclusive fish that is rarely seen by scuba divers. As a result, very little is known about its behavior. In this report we will share some observations on the comet’s egg-tending behavior and give ideas on how to capture it on film.

Lions of the Reef

The lionfishes are some of the most beautiful fishes found on the coral reef. They are a favorite of divers and aquarists alike. Check out this gallery of 12 different species/variants with info and photos.

Frogfish Fever

Grips the Strait!

CoralRealm corespondents give a first-hand report of new discoveries and fascinating finds in the Lembeh Strait.